1. Field of the Invention
The present invention relates in general to the control of a model vehicle such as a model toy train and more particularly to a control for operating features of the same.
2. Description of the Related Art
Model train enthusiasts have always desired the ability to control a number of functions of one or more model trains on a track. Early trains had only a single feature, the motor of the train was “on” or it was “off.” In the typical modern system, the train engine is an electrical engine receiving power from the train tracks. The train motor typically picks up the power from a voltage applied to the tracks through contacts on the bottom of the train or through train wheels. The amplitude and polarity of the voltage applied to the tracks controls the speed and direction of the train. In HO systems, this voltage is a direct current (DC) voltage. More commonly, particularly for O-gauge systems, this voltage is an alternating current (AC) voltage. In conventionally controlled AC voltage systems, in order to change the direction of the train, the AC signal is removed and reapplied to the track.
One approach for controlling on-board functions of a train is to superimpose a DC voltage on top of such an AC track voltage applied to the track. The applied DC voltage forms a DC offset on the track (i.e., the AC track voltage is normally “balanced”). The DC offset is detected by a DC receiver mounted on the train, activating an onboard device, such as a whistle or the like. Trains so equipped are responsive to track power changes and a single DC offset. A later improvement included applying DC offsets of different polarities and amplitudes, increasing the number of on-board functions that could be implemented. In the O-gauge market, model trains responsive to changes in track power (for control of the speed) and DC offsets (for control of the features or functions) are referred to as being controlled in a conventional mode.
U.S. Pat. Nos. 4,914,431, 5,184,048 and 5,394,068 issued to Severson et al. disclose a method of increasing the number of control signals available by the incorporation of a state machine in the train. Model trains responsive to this method may include a state machine whereby a plurality of key presses of a remote control device change the state of the state machine and activate a feature of the train associated with that state. However, use of this system may require that the user learn a sequence of key presses.
More recently, so-called command control techniques have been applied to model trains. For example, U.S. Pat. Nos. 5,251,856, 5,441,223 and 5,749,547 to Young et al. disclose, among other things, providing a digital message, which may include a command, to a model train using various techniques. The digital message(s) so produced are typically read by a decoder mounted on the train, which then executes the decoded command. Operating such a system involves manipulating a remote control and some particularly advanced features may require programming.
Other systems have been introduced, but have been perceived as difficult to program by some users, particularly when model trains associated with different control systems are used on a common track. Because of the perception by certain users, many model toy trains with such internal electronics are run on layouts without the associated controls needed to actually activate those electronics. Instead, a transformer merely supplies power to the tracks and the model train is operated in conventional mode. Thus, in some circumstances, the advanced operating features of these modern model trains are not fully utilized.
Therefore, a need exists for a system that minimizes or eliminates one or more of the problems or challenges noted in the Background.